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Problems with tin and copper antifouling compounds have highlighted the need to develop new environmentally friendly antifouling coatings. Bacteria isolated from living surfaces in the marine environment are a promising source of natural antifouling compounds. Four isolates were used to produce extracts that were formulated into ten water-based paints. All but one of the paints showed activity against a test panel of fouling bacteria. Five of the paints were further tested for their ability to inhibit the settlement of barnacle larvae, Balanus amphitrite, and algal spores of Ulva lactuca, and for their ability to inhibit the growth of U. lactuca. Two paints caused a significant decrease in the number of settled barnacles. One paint containing extract of Pseudomonas sp. strain NUDMB50-11, showed excellent activity in all assays. The antifouling chemicals responsible for the activity of the extract were isolated, using bioassay guided fractionation, and their chemical structures determined.

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In a 2.5-year-long environmental engineering experiment in the By Fjord, surface water was pumped into the deepwater where the frequency of deepwater renewals increased by a factor of 10. During the experiment, the deepwater became long-term oxic, and nitrate became the dominating dissolved inorganic nitrogen component. The amount of phosphate in the water column decreased by a factor of 5 due to the increase in flushing and reduction in the leakage of phosphate from the sediments when the sediment surface became oxidized. Oxygenation of the sediments did not increase the leakage of toxic metals and organic pollutants. The bacterial community was the first to show changes after the oxygenation, with aerobic bacteria also thriving in the deepwater. The earlier azoic deepwater bottom sediments were colonized by animals. No structural difference between the phytoplankton communities in the By Fjord and the adjacent Havsten Fjord, with oxygenated deepwater, could be detected during the experiment.Electronic supplementary materialThe online version of this article (doi:10.1007/s13280-014-0524-9) contains supplementary material, which is available to authorized users.

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To assess the short-term trend of pollution by hexachlorobenzene (HCB), chlorophenols, and polychlorinated biphenyls (PCB) emitted to a marine environment, existing and former loads were estimated based on pollutant concentrations in water, blue mussels, and sediment, using partitioning calculations. The study included chemical analyses of organochlorines in sediment samples, caged mussels, and semipermeable membrane devices (SPMD) incubated in the water column and in the outflow from an adjacent plant in order to find out whether the high pollutant concentrations found in the superficial sediment corresponded to former or existing discharges. A comparison was made of hypothetical water concentrations calculated from values determined in SPMDs, mussels, and sediment, assuming equilibrium in the distribution of the pollutants between mussels and water or sediment and water. Sediment-derived water concentrations of HCB in the vicinity of the outlet were much higher than the water concentrations calculated from SPMDs or mussels, indicating that the discharges of HCB from a local source were strongly reduced during the past decade. It is concluded that partitioning calculations applied on analytical data from mussels and superficial sediment, when combined with SPMD data, make possible the detection of short-term changes of environmental loads of hydrophobic pollutants.

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